It's not happening only at high voltages.
For example, set the BIOS to 1.5V and see your voltage going to 1.3xxV during the black screen/welcome screen process.

OV_CPU has nothing to do with that, as it happens with both the OV_CPU mod done and unmodded.
And of course OV_CPU is done the way I posted some pages back, pin 1 & 2 = enable, pin 2 & 3 = disabled ( or just don't solder anything ).